I'm a scripting noob, but I managed this much:
;Artificial Intelligence Script
;Header
desc = Walk into zone and display HUD
;Triggers
:state=0:hudreset,hudx=50,hudy=50,hudimagefine=XXX,hudname=pix1,hudhide=1,hudmake=display,state=10
:state=10,plrwithinzone=1:hudshow=pix1,hudfadeout=pix1
;End of Script
Replace the "XXX" with the picture file location. You'll have to make a new scipt every time you want this effect, and if you do you need to change the 3 occurences of "pix1" tp "pix2" or whatever you want.
You use this with a trigger zone.
Watch out, this bunny bites...